SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c7c5ef40857636f948f727f301cd1ba1abf186357bf0a488c6d3c62bfc36fb71' 
  AND token = 'iF2AcT2GH3OfBvjnVI902PaW+4Ga5RSjkhuXTl10EWM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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