SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '34e395a5aebb622f8bb2f643328aa0eba69d05f3715ae6a024751fc5053d5b95' 
  AND token = 'gblFDrgS2jdqPDrhR5BYkt0OW8CoCZcZ4W2L/1kgHow=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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