SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0b5ac974278f460bc5d1c7a18d3128ff40093eac3dd1f63bb6d98e14dd14aeaa' 
  AND token = 'drLDNOT8UvTV/UBlmzyaY4AwuriK1r3VrSjQFOq6gCY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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