SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '65e1bba044fe523291918eb16f0f37c75c25082b0401541feb18cbd7553713f5' 
  AND token = 'zKR7vIx/+AT1mK2+wkU/Ol1S2ihjIwWfOh1kVUMUsKw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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