SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c62a015fecded740defdc447782d401187dcfe20be07b6b6320fd2d5e395faa8' 
  AND token = 'wYnnjaKmMC1CZ6peVb3WOXXvDpJp8WjXtt0g+bJ9Ze0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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