SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7ea1fbf9606617be6e8779fb82ff5f328d6af7386a92b713474a911b2fa45170' 
  AND token = '0tBn1pwi7Ngj87C4z7VV0Gi5oTe/lyFrE+PrdI+SmkE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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