SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9553173a00afc9eba83fe68ec2a745c46a2af58bff1484bd6d851891439c6230' 
  AND token = 'Zcaa7jGAD23PhMOkP+z6MrgNyeZdoBe1yccPRG18WKs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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