SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '105b93956115dab4509c93639f9b872856090c39d045501af5346c12cf0169a0' 
  AND token = 'fuKYPCSG6zVBLSVZuv+do4DiXWFSnCJK1tpybirYNpM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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