SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f035964e7bd6270aa52f317063c20117bfc6eff374e55f986d5af2cd88e2cac3' 
  AND token = '0hWNCAKeJOeaEwWYsUgRVjzp29biAS/7VsAoZZQ1qfQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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