SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e1ba44fa473f7b7105be066b6cca663641ccd3cd76a8628b4df6ba07e1ceafe1' 
  AND token = 'lL1mlbsHUiPBcsTzOzVSFr/6Ye+pk4x5IWiN/NAP6C8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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