SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c1c93716a008bd941ed39272e8fbc286b6d500cfbfa7f433958c0cbdf3dd5acc' 
  AND token = 'W9/KnihFWRIP13/w35xkka+erxITxHwgMXhEUIbP7+A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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