SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a05c46feb286582b6ad799b45051547d5aa2d696be53870e6c534d01ddd6a40e' 
  AND token = 'jsOEqNm0f3SuZgXTrj/1BhlJFI47eqUrPevg0kqYdfY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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