SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'dbcfaf0a6f092da975b42921c7b5f1793e42e0e60e9c279aad62d41a142a9948' 
  AND token = 'bI90YWKLJHxUX5ukSor37oKoYxpX1O0il1kcs8SBjPE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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