SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3418eb5ce965463b28c9fd0c3d1eedee47044097a227a253209b8af4d398382a' 
  AND token = 'IoLD0j6NRs+jRC6mRy2YADcBI79lYKtKqRBXWVaXf0o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00056

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}