SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0e67ae77257e25c482d3a92082f0f1dcee616177f47208d631b380149fec219b' 
  AND token = 'RXJOGKOuygCcadytKPgqXfKaA9rd/FiiUPi9ZUJItRQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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