SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5e29d62b98da9b5ff25e6033116fac6549c6368affda3a880ae137a760c30b1d' 
  AND token = 'UmAw4XvgGSp/wUvskKWy0tG2HrVHyqrb5pxsLzm+A68=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}