SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f114d9ed1943882bb58732baabf5deb41e11ddefd2aa0d5f8f0c77032f5c1fad' 
  AND token = '92rCurq5RVGDVr/h+ZdM1rS6myQvYIhqNuPgiVD1mB8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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