SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fdee4294369c763b5154924e9518f94bf7f3a2914ab34b183f83297d67be2c6d' 
  AND token = 'uHO6Z8opnnLwnjaY+g8vpIFmPPfjx++3thlDGXMjNxk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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