SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3ef72682adf53f840df68fcea7844a195e492a85bad03ebebd51fe15380a9335' 
  AND token = 'inZke9ZFWOLxweS14RWZR2djOcglX1qEJA/8f1Pg4ok=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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