SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e16ad8b9639096a4317a8953679a7eb55260204f59c009e97a34e2b15bec725e' 
  AND token = 'bykfkzGNdiqsXroPIyCoelvv+HR0azDG5RwIdVkksvE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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