SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bacfb7a0b5e9d07db17b5af683cc205aedbcb7627769bd7432088fd342dabe20' 
  AND token = '4oxnMuWYit5ye/ORjPHoDGwSyWrpcGkNVEmJnHuZZ4w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}