SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '41b54864d9f29384bdb1fdd3bd8abbc4d0b21b878878dc4e7b33202144fa3a4c' 
  AND token = 'GY21FbWD/zWkES4/f0+jr/znQZyaECJOTOfdWk3WsQc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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