SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a54eb6a0ccc64b9b94c7fb5c307929aba15487480b3ef50f244070ed2743e808' 
  AND token = 'Gt/KEQV8eTwdy5msm0vbc0jQV2r9cxtuoyTwLxjjHoM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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