SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4a20f05772c6d2ff40aa671501010d9d315b93a4aa47b4a01749e528595da604' 
  AND token = 'yMfMRLIRVUuCOqY5tlQC+1uc8lvouF56/FoIVUo8ae4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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