SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '863c7e0be033c4eb65049ee09d437c769ab3e91c2eca1f84d6b2d2c3906ba93c' 
  AND token = 'WN3D+TurtOTTTsMBSulK32o4y/RMluKmaVSgJlWM6V0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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