SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '86ee61a88e8cfbeeb4dceaeed007025ce0d1a14fc951a5be42b3a8bafb742a70' 
  AND token = 'bzcmbadhsqQyl2WmuAYmZhJVhuDBnbpdetaokxqReNg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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