SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aa08c0834a0fb198455ed7ab2a6ef1c9a189e7c13a2329fe324190c41a9a30a5' 
  AND token = 'WyO4X15EipwWSumX3TV750dLKN1gIwBnrEFCu9vF28c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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