SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '73299826cef01e8b8595fdb41b776b97f747ced124384aca53c4471fa84d50e6' 
  AND token = 'Xzq84V3r/4eFXfLTPAJhrAvrmY/VjhrJyc4MAx21LZs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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