SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f19d3add614935f0b6e6211bfe9bf6c1622e80b23f4008dc67d1977fa206b06e' 
  AND token = 'qIjS/jpcIHap56Rf2YgV/+kSz6Wy5z5++PKVgzwVolU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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