SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cca38e959b6118290e50a26caed3ca3b0d3691674621486a6ee9b3925579ee41' 
  AND token = 'Be0t9jMTk+nASzpEKyJnDA9ahWpN3Hx9OL5mbukvVnA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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