SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd1c7afb0dd0121c83a082320f97aba13179da408aaba1943ac63f79fab03fab3' 
  AND token = 'xMFl2+aZ7MxsiMszFXEAGNZ1WBF1kao6tnXmfBNWHyc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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