SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e2235ba282033487c00fbd19a8ad09a9fc55ae4cda4f2a0754236eaee0e60209' 
  AND token = 'IRN8A+4i2A3K8vI9YjlJZFIuBEavHicQuUf0biSTerM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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