SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '433b9a38f4a5b9f81aecf20743c24938b8124096bed7bd5050eaf2fe3445b6e1' 
  AND token = 'ZIejJOoQ6LdVDqTjLbdjqU7aiN4ildnX930zim2HLLc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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