SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4c952fa0b874ba8b2e1d5cefe5be3cfdcd798820415fe63a420313cc035a96ed' 
  AND token = 'P84c1DmyWvcG3oDMqM8lfGlzSUThYYP8ukhz7e2x6Z4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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