SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b13188d76a408eceaa258bda3282263d482cc29ff06c4800856a2e716f7a9522' 
  AND token = 'BWgWOcQaZnnrFikHktrSpK96DtThQVjMWlYii/lE4u0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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