SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4c5fc70a1793e060c2910cb14d4c54ac86f465d920c92190837948b85f33d17b' 
  AND token = 'gleTM0lk1O5QUL3XfVi2V7CUTyWLH3DXWJwvMz9+UKA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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