SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7a4c507fbd80c6d501b138ae96a538026cf1193807158cf4085715a57aa9d5d6' 
  AND token = 'QDLR1pl06754PkQC2A+bhpoMxjzvhgbTnOZXVqIy0qM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}