SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7c5ea5d15fcf91e8826058c5b08b3524381a2a33485a065e5c0265072c40c714' 
  AND token = 'FkyQC5LkYzNEd4QGZNbsKHsX08dOyN6oovdAVZIphUM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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