SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '04e4bf8bc41fa04292f33d9487bd964d94b86f70ad9faeb31434ab3bbb02ea27' 
  AND token = 'Od9NJShDHj0Fwz+Tm5bSp/kk2vVbwVPabSdeQOEZgWk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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