SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0dd5b10595d6a14601e1c15c4a03d62b3b71c142ef06599a57c47c53a0d19995' 
  AND token = 'B6lGq1XIN3JR9XfhWCd9zmoCHMISKXV9KpegL2IuFEM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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