SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6f4ffb852bb0c0d50b312f984382f0460f5db94004e70b79fadc35a369d38b0c' 
  AND token = 'ptNe60wGFGAcfPy+a3EiPLCH8Ipfhu07tp1Ju3FIUas=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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