SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '22828cabf041ab40c60c66269d3c791384990b10a66c50e5583a77378ecd1040' 
  AND token = 'JmduFHLvK9TOZUq4dl5MCep5WIbxfqVld3t7nBFXkIM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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